It is disclosed in, for example, “Principles of Computerized Tomographic Imaging”, Kak, Slaney, IEEE Press, 1999, that a computed tomography system comprises an X-ray source for generating X-rays and a detector. The X-ray source and the detector rotate around a region of interest while the X-rays generated by the X-ray source traverse through the region of interest and are detected by the detector for acquiring projection data. An image of the region of interest is reconstructed by using a reconstruction algorithm which, for example, filters and backprojects the acquired projection data. The reconstructed images generally show image artifacts.